JP6930577B2 - Method for producing fluoroethane and method for producing fluoroolefin - Google Patents

Description

The present disclosure relates to a method for producing fluoroethane and a method for producing a fluoroolefin.

Fluoroethane represented by 1,1,2-trifluoroethane (hereinafter referred to as "HFC-143") is known as a raw material for producing various refrigerants. Various methods have been proposed as methods for producing fluoroethane such as HFC-143.

For example, Patent Document 1 proposes a technique for producing HFC-143 by a hydrogenation reaction of chlorotrifluoroethylene or the like in the presence of a hydrogenation catalyst.

Japanese Unexamined Patent Publication No. 1-287044

However, for example, when fluoroethane such as HFC-143 is produced by the method disclosed in Patent Document 1, there is a problem that the selectivity of the target product is deteriorated.

The present disclosure has been made in view of the above, and an object of the present disclosure is to provide a method for producing fluoroethane and a method for producing fluoroolefin, which have a high selectivity for fluoroethane, which is a target product.

The present disclosure includes, for example, the inventions described in the following sections.
Item 1
The following general formula (1)
CX ¹ X ² FCX ³ X ⁴ X ⁵ (1)
(In formula (1), X ¹ , X ² , X ³ , X ⁴ and X ⁵ are the same or different and represent hydrogen, fluorine or chlorine atoms, X ¹ , X ² , X ³ , X ⁴ and at least one of X ⁵ represents a hydrogen atom)
It is a method for producing fluoroethane represented by
Depending on the reaction in the presence of a catalyst, the following general formula (3)
CX ⁹ F = CX ¹⁰ X ¹¹ (3)
(In formula (3), X ⁹ , X ¹⁰ and X ¹¹ represent the same or different hydrogen atom, fluorine atom or chlorine atom).
The catalyst comprises a step of obtaining a product containing the fluoroethane from fluoroethylene represented by, and the catalyst is formed by supporting a noble metal on a carrier.
The reactor in which the reaction is carried out is filled with a catalyst having a noble metal concentration of C1% by mass based on the entire catalyst and a catalyst having a noble metal concentration of C2% by mass based on the entire catalyst, respectively. A part is formed and C1 <C2.
A method for producing fluoroethane, wherein the reaction is carried out by bringing fluoroethylene and hydrogen gas represented by the formula (3) into contact with each other in the order of the upstream portion and the downstream portion.
Item 2
Item 2. The method for producing fluoroethane, wherein the noble metal is palladium.
Item 3
Item 3. The method for producing fluoroethane according to Item 1 or 2, wherein the fluoroethylene represented by the formula (3) contains chlorotrifluoroethylene.
Item 4
Item 3. The method for producing fluoroethane according to any one of Items 1 to 3, wherein the fluoroethane contains 1,1,2-trifluoroethane.
Item 5
Item 4. The production method according to Item 4, wherein the product contains 60 mol% or more of 1,1,2-trifluoroethane based on the total amount of the product.
Item 6
Item 8. The production method according to any one of Items 1 to 5, wherein the product contains 40 mol% or less of trifluoroethylene based on the total amount of the product.
Item 7
A method for producing a fluoroolefin, comprising a step of obtaining a fluoroolefin by a defluorination hydrogen reaction of fluoroethane obtained by the production method according to any one of Items 1 to 6.

According to the production method of the present disclosure, fluoroethane, which is a target product, can be obtained with a high selectivity.

In the method for producing fluoroethane, the present inventors have produced many fluoroethanes such as HFC-143 (1,1,2-trifluoroethane) according to the method disclosed in Patent Document 1, for example. In this case, we found that the selectivity of the target product, fluoroethane, was poor. Moreover, it was also confirmed that in the method disclosed in Patent Document 1, clogging and corrosion of the reactor occur remarkably during the reaction. In particular, when the capacity of the reactor was increased (that is, when scaled up for mass production), the selectivity was more significantly reduced, and the reactor was blocked and corroded during the reaction.

Therefore, the present inventors have conducted intensive studies to achieve the object of providing a production method in which the selectivity of fluoroethane, which is a target product, is high and the reactor is less likely to be clogged and corroded. As a result, it has been found that in a catalyst in which a noble metal is supported on a carrier, the above object can be achieved by inclining the amount of the noble metal supported.

Hereinafter, embodiments included in the present disclosure will be described in detail. In addition, in this specification, the expressions "contains" and "includes" include the concepts of "contains", "includes", "substantially consists" and "consists of only".

1. 1. Method for Producing Fluoroethane In the method for producing the present disclosure, the following general formula (1)
CX ¹ X ² FCX ³ X ⁴ X ⁵ (1)
(In formula (1), X ¹ , X ² , X ³ , X ⁴ and X ⁵ are the same or different and represent hydrogen, fluorine or chlorine atoms, X ¹ , X ² , X ³ , X ⁴ and at least one of X ⁵ represents a hydrogen atom)
Manufactures fluoroethane represented by.

In the production method of the present disclosure, the following general formula (3) is used depending on the reaction in the presence of a catalyst.
CX ⁹ F = CX ¹⁰ X ¹¹ (3)
(In formula (3), X ⁹ , X ¹⁰ and X ¹¹ represent the same or different hydrogen atom, fluorine atom or chlorine atom).
Including the step of obtaining the product containing the fluoroethane from the fluoroethylene represented by.

Hereinafter, in the present specification, the method for producing fluoroethane of the present disclosure will be referred to as "the production method 1 of the present disclosure".

In particular, in the production method 1 of the present disclosure, the catalyst is formed by supporting a noble metal on a carrier. Further, the reactor in which the hydrogenation reaction is carried out is filled with a catalyst having a noble metal concentration of C1% by mass based on the entire catalyst and a catalyst having a noble metal concentration of C2% by mass based on the entire catalyst. An upstream portion and a downstream portion are formed, and C1 <C2. The hydrogenation reaction is carried out by bringing fluoroethylene and hydrogen gas represented by the formula (3) into contact with each other in the order of the upstream portion and the downstream portion.

In the production method 1 of the present disclosure, the target product is fluoroethane represented by the formula (1) (hereinafter, simply referred to as "fluoroethane"). In addition to the fluoroethane, by-products can also be produced in the production method 1 of the present disclosure. Therefore, the product may be a mixed gas of the target product and the by-product.

In the production method 1 of the present disclosure, the by-product is, for example, the following general formula (2).
CX ⁶ F = CX ⁷ X ⁸ (2)
In formula (2), X ⁶ , X ⁷ and X ⁸ represent the same or different hydrogen atom, fluorine atom or chlorine atom, ^{and at least one of X 6} , X ⁷ and X ⁸ represents a hydrogen atom. ) Is fluoroethylene.

In the production method 1 of the present disclosure, fluoroethane, which is a target product, can be obtained with a high selectivity. Moreover, in the production method 1 of the present disclosure, it is possible to prevent the reactor from being blocked and corroded during the hydrogenation reaction.

(Product)
In the production method 1 of the present disclosure, the fluoroethane contained in the product is the main product and the target product of the production method 1 of the present disclosure. The main product referred to here means a component contained in the product in an amount of 50 mol% or more.

The fluoroethane is not particularly limited as long as it is a compound represented by the formula (1). In formula (1), ^{at least one of X 1} , X ² , X ³ , X ⁴ and X ⁵ represents a hydrogen atom, and for example, X ⁵ can be a hydrogen atom. It is preferable that at least one of X ¹ , X ² , X ³ , X ⁴ and X ^{5 is a fluorine atom.}

As further specific examples of the fluoroethane, 1-chloro-1-fluoroethane (HCFC-151), fluoroethane (HFC-161), 1,2-dichloro-1,2-difluoroethane (HCFC-132), 2 −Chloro-1,1-difluoroethane (HCFC-142), 1-chloro-1,2-difluoroethane (HCFC-142a), 1,2-difluoroethane (HFC-152), 1,1-difluoroethane (HFC-152a) , 2-Chloro-1,1,2-trifluoroethane (HCFC-133), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1,1,1-trifluoroethane (HFC) -143a), 1,1,2-trifluoroethane (HFC-143), 1,1,2,2-tetrafluoroethane (HFC-134) and 1,1,1,2-tetrafluoroethane (HFC-). At least one selected from the group consisting of 134a) is exemplified.

In the production method 1 of the present disclosure, one kind or two or more kinds of the fluoroethanes are produced. That is, in the production method 1, the product contains one or more of the fluoroethanes. The fluoroethane, which is the main product of the production method 1 of the present disclosure, more preferably contains at least 1,1,2-trifluoroethane (HFC-143), and 1,1,2-trifluoroethane (HFC). It is particularly preferable that 143) is the main product. When 1,1,2-trifluoroethane (HFC-143) is the main product, for example, HCFC-133 and HCFC-133b may be produced at the same time.

Among the by-products produced by the production method 1 of the present disclosure, the fluoroethylenes represented by the formula (2) include trifluoroethylene (HFO-1123) and 1,2-difluoroethylene (HFO-1132). ), 1,1-difluoroethylene (HFO-1132a), fluoroethylene (HFO-1141), 1-chloro-2-fluoroethylene, 1,2-dichlorofluoroethylene (HCFO-1121). It is preferable to contain at least one type. Of these, the fluoroethylene represented by the formula (2) is particularly preferably containing trifluoroethylene (HFO-1123). The by-products produced by the production method 1 of the present disclosure are one kind or two or more kinds.

In the production method 1, the product preferably contains 60 mol% or more of 1,1,2-trifluoroethane, more preferably 70 mol% or more, and 80 mol% based on the total amount of the product. It is particularly preferable to include the above.

In the production method 1, the product preferably contains 40 mol% or less of trifluoroethylene, more preferably 30 mol% or less, and particularly preferably 20 mol% or less, based on the total amount of the product. ..

In the production method 1, the product may be purified to increase the purity of the target compound, or the product obtained without purification may be used as the target compound. When the product contains an unreacted raw material, the raw material can be used again as a raw material for the reaction by separating the raw material by an appropriate method. That is, in the production method 1, the crude product can be used for recycling the raw material.

(material)
In the production method 1 of the present disclosure, the fluoroethylene represented by the formula (3) is a raw material for obtaining a target product, and is a raw material for the reaction carried out in the production method 1 of the present disclosure. The fluoroethylene represented by the formula (3) can be appropriately selected according to the structural formula of the target fluoroethane.

For example, examples of the fluoroethylene represented by the above formula (3) include fluoroethylene (HFO-1141), 1,2-dichloro-1,2-difluoroethylene (CFO-1112), and 1,1-difluoroethylene (HFO). -1132a), 1,2-difluoroethylene (HFO-1132), chlorotrifluoroethylene (CTFE, CFO-1113), trifluoroethylene (HFO-1123), 2-chloro-1,1-difluoroethylene (HCFO-) It is preferably at least one selected from the group consisting of 1122), 1-chloro-1,2-difluoroethylene (HCFO-1122a) and tetrafluoroethylene (FO-1114). Of these, the fluoroethylene preferably contains at least one selected from the group consisting of chlorotrifluoroethylene (CTFE, CFO-1113) and tetrafluoroethylene (FO-1114), and more preferably chlorotrifluoroethylene. It is particularly preferable to include (CTFE, CFO-1113).

The fluoroethylene represented by the formula (3) can be used alone or in combination of two or more. When the fluoroethylene represented by the formula (3) is used alone, the fluoroethylene may contain, for example, impurities that may inevitably exist or other components.

(catalyst)
In the production method 1 of the present disclosure, fluoroethylene represented by the formula (3) is subjected to the reaction in the presence of a catalyst. As will be described later, the reaction is, for example, a hydrogenation reaction, a dehydrochlorination reaction accompanying the hydrogenation reaction, and a hydrogen chloride addition reaction.

In the production method 1 of the present disclosure, the type is not particularly limited as long as a catalyst formed by supporting a noble metal on a carrier is used, and for example, a known catalyst used in a hydrogenation reaction is widely used. be able to.

In the catalyst used in the production method 1 of the present disclosure, examples of the noble metal include palladium (Pd), platinum (Pt), ruthenium (Ru), rhodium (Rh), nickel (Ni), cobalt (Co) and the like. Can be mentioned. The noble metal is preferably one or more selected from the group consisting of palladium, platinum and nickel, and particularly preferably contains palladium.

In the catalyst used in the production method 1 of the present disclosure, examples of the carrier include activated carbon, porous aluminosilicate typified by zeolite, aluminum oxide, silicon oxide, titanium oxide, zirconia oxide, zinc oxide, aluminum fluoride and the like. Can be mentioned. The carrier can be formed of only one material, or can be formed of two or more materials.

In the production method 1 of the present disclosure, particularly, in the reactor in which the reaction is carried out, the concentration of the noble metal with respect to the total mass of the catalyst is C1% by mass, and the concentration of the noble metal with respect to the total mass of the catalyst is C2% by mass. The former is formed as an upstream portion and the latter as a downstream portion by filling with the catalyst. Here, C1 <C2.

In this way, the catalyst in the upstream portion and the catalyst in the downstream portion are formed, respectively, and the reaction is carried out by bringing the fluoroethylene and hydrogen gas represented by the formula (3) into contact with each other in the order of the upstream portion and the downstream portion. Therefore, the upstream portion and the downstream portion referred to in the present disclosure refer to the inlet side and the outlet side into which the fluoroethylene represented by the formula (3), which is a raw material, is input, respectively.

In the production method 1 of the present disclosure, the positions where the upstream portion and the downstream portion are provided in the reactor are not particularly limited. For example, the upstream portion and the downstream portion can be provided adjacent to each other, or the upstream portion and the downstream portion can be provided at intervals. A catalyst may be further filled between the upstream portion and the downstream portion to form a midstream portion. The midstream portion can be formed with only one layer, or can be formed with two or more layers. In the catalyst forming the middle stream portion, when the noble metal concentration of the catalyst ^{is expressed as CM} mass%, C1 < ^CM <C2 can be set.

The thickness of the upstream portion and the downstream portion is not particularly limited, and can be appropriately selected depending on the size of the reactor, the flow rate of the gas, and the like. The thickness of the upstream portion and the downstream portion means the length with respect to the direction in which the raw material flows.

In the upstream portion, the amount of the noble metal supported on the total mass of the catalyst, that is, C1 (mass%) can be adjusted to, for example, 0.01 to 10% by mass, and is adjusted to 0.1 to 3% by mass. Is preferable.

In the downstream portion, the amount of the noble metal supported on the total mass of the catalyst, that is, C2 (mass%) can be adjusted to, for example, 1 to 15% by mass, and preferably 1 to 5% by mass.

The method for preparing the catalyst is not particularly limited, and a known preparation method can be widely used. For example, in a catalyst in which a noble metal is supported on a carrier, the carrier is impregnated with the carrier by immersing the carrier in a solution containing the noble metal, and then, if necessary, neutralization, calcination, or the like is performed. Obtainable. In this case, the amount of the noble metal supported on the carrier can be controlled by adjusting the concentration of the solution, the impregnation time, and the like.

In the production method 1 of the present disclosure, the amount of the catalyst used is not particularly limited, and for example, it can be the same as a known hydrogenation reaction. For example, it can be appropriately set according to the size of the reactor, the amount of the raw material used, the amount of fluoroethane to be produced, and the like.

(reaction)
In the production method 1 of the present disclosure, the reaction is, for example, a hydrogenation reaction. Further, in the production method 1 of the present disclosure, the reaction may include one or both of the dehydrochlorination reaction and the hydrogen chloride addition reaction in addition to the hydrogenation reaction.

In the production method 1 of the present disclosure, the reaction is carried out by reacting fluoroethylene represented by the formula (3) with hydrogen gas in the presence of a catalyst in a reactor. Usually, the reaction is carried out in the gas phase. Further, in the production method 1 of the present disclosure, either a continuous method or a batch method can be adopted for the reaction.

Specifically, in the production method 1 of the present disclosure, the hydrogenation reaction proceeds by inflowing fluoroethylene and hydrogen gas represented by the formula (3) into the reactor filled with the catalyst and bringing them into contact with the catalyst. Further, the dehydrochlorination reaction and the hydrogen chloride addition reaction accompanying the hydrogenation reaction can also proceed. At this time, the fluoroethylene and the hydrogen gas pass through the catalyst while contacting the catalyst in the upstream portion and the catalyst in the downstream portion in this order, flow through the reactor, and then generate a target fluoroethane containing the target fluoroethane outside the reactor. Objects are collected, for example, as a mixed gas. In addition to the target product, fluoroethane, the mixed gas may also contain the above-mentioned by-products, for example, fluoroethylene represented by the formula (2).

In the production method 1 of the present disclosure, when either one or both of the dehydrochlorination reaction and the hydrogen chloride addition reaction proceeds as a side reaction during the hydrogenation reaction, the formula (fluoroethane, which is the target product, and the formula ( By-products such as fluoroethylene represented by 2) can be produced.

As the reactor, for example, a tube-type flow reactor or the like can be used. As the distribution type reactor, for example, an adiabatic reactor, a multi-tube reactor cooled by using a heat medium, or the like can be used. The reactor is preferably made of a material resistant to corrosive action such as stainless steel (SUS), and in particular, made of Hastelloy, INCONEL, MONEL, or the like. Is preferable.

The reactor may also be provided with a jacket for adjusting the temperature inside the reactor, and for example, a heat medium or the like can be circulated in the jacket. Thereby, the temperature of the gas (for example, fluoroethylene and hydrogen which are raw materials) in the reactor can be adjusted.

In the production method 1 of the present disclosure, the reaction may be carried out under reduced pressure, atmospheric pressure or pressurization. For example, in the production method 1 of the present disclosure, from the viewpoint of reactivity, the pressure at the time of reaction is preferably 2 MPaG or less, more preferably 1 MPaG or less, and particularly preferably 0.3 MPaG or less. In addition, G of "MPaG" means that it is a gauge pressure, and shows the display value of the pressure gauge with atmospheric pressure as a reference (that is, atmospheric pressure as 0 MPaG). The reaction can also be carried out in the presence of either an inert gas or air.

In the production method 1 of the present disclosure, the reaction temperature in the upstream portion (atmospheric temperature when the raw material comes into contact with the upstream portion) can be 100 to 500 ° C, preferably 200 to 400 ° C. Further, in the production method 1 of the present disclosure, the reaction temperature in the downstream portion (atmospheric temperature when the raw material comes into contact with the upstream portion) may be appropriately adjusted to the temperature in the downstream portion according to the type of the target product. It can be, for example, 100 to 400 ° C, preferably 150 to 300 ° C. The temperature of the upstream portion is preferably 400 ° C. or lower from the viewpoint of preventing polymerization, explosion, catalyst deterioration, etc. of the raw material fluoroethylene, and the temperature can be adjusted by cooling as necessary.

In the production method 1 of the present disclosure, the amount of hydrogen gas used in the reaction is not particularly limited, and can be, for example, the same as a known hydrogenation reaction. For example, the amount of hydrogen gas can be adjusted to 1 to 25 mol with respect to 1 mol of fluoroethylene represented by the formula (3) as a raw material. The hydrogen gas is preferably 1 to 15 mol, more preferably 1 to 10 mol, with respect to 1 mol of the fluoroethylene represented by the formula (3).

In the production method 1 of the present disclosure, the reaction time of the hydrogenation reaction is not particularly limited. For example, the ratio of the filling amount of the catalyst in the reactor to W (g) and the total flow rate of fluoroethylene and hydrogen gas flowing into the reactor to Fo: the contact time expressed in W / Fo is 1 to 100 g. It can be sec / cc.

The production method 1 of the present disclosure may include, if necessary, other steps in addition to the step of obtaining the fluoroethane.

In the production method 1 of the present disclosure, the catalyst filled in the reactor forms the upstream portion and the downstream portion, so that the fluoroethylene and hydrogen gas represented by the formula (3) have low activity catalysts. It passes first, and then passes through the downstream catalyst, which is more active than the upstream catalyst. This makes it easier to suppress the fluoroethylene polymerization reaction that has occurred as a side reaction in the conventional method, and as a result, the excessive temperature rise in the reactor and the amount of fluoroethylene polymer produced are significantly suppressed. NS. In addition, the amount of intermediate products and by-products of the hydrogenation reaction mixed in the finally obtained fluoroethane can be remarkably suppressed. Therefore, in the production method 1 of the present disclosure, the selectivity and yield of the product can be controlled by the catalyst in the downstream portion and the reaction temperature. Further, by adjusting the reaction conditions, a mixture of fluoroethylene and fluoroethane can be obtained with a high conversion rate and a high selectivity.

Further, conventionally (for example, in the case of the method disclosed in Patent Document 1), in addition to the problem of poor selectivity of the target product, there is also a problem of causing blockage and corrosion of the reactor. However, the production method 1 of the present disclosure has an advantage that the polymerization reaction of fluoroethylene is likely to be suppressed, so that the reactor is less likely to be clogged and corroded due to the formation of the polymer.

In the production method 1 of the present disclosure, the intermediate product of the hydrogenation reaction is, for example, trifluoroethylene when chlorotrifluoroethylene is used as a raw material. In the production method 1 of the present disclosure, the by-products of the hydrogenation reaction are, for example, 1-chloro-1-fluoroethane (HCFC-151) and fluoroethane (HFC-) when chlorotrifluoroethylene is used as a raw material. 161), chloro-1,2-difluoroethane (HCFC-142), 1,2-difluoroethane (HFC-152), 1,1-difluoroethane (HFC-152a), 2-chloro-1,1,2-trifluoro Etan (HCFC-133), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1,1,1-trifluoroethane (HFC-143a), trifluoroethylene (HFO-1123), One or more selected from 1,1-difluoroethylene (HFO-1132a), 1,2-difluoroethylene (HFO-1132), ethylene, chloroethane and the like.

Since fluoroethane can be produced with a high selectivity in the production method 1 of the present disclosure, HFC- used as a raw material for producing 1,2-difluoroethylene (HFO-1132), which is promising as a post-R32 refrigerant. It is particularly useful as a method for producing 143.

2. Method for Producing Fluoroolefin The method for producing a fluoroolefin of the present disclosure includes a step of obtaining a fluoroolefin by a defluorination hydrogen reaction of fluoroethane obtained by the above-mentioned method for producing fluoroethane (production method 1). Hereinafter, the step is abbreviated as "hydrogen defluorination step", and the method for producing a fluoroolefin of the present disclosure is referred to as "the production method 2 of the present disclosure".

According to the manufacturing method 2 of the present disclosure, for example, the following general formula (4)
CX ¹¹ X ²¹ = CX ³¹ X ⁴¹ (4)
(In formula (4), X ¹¹ , X ²¹ , X ³¹ and X ⁴¹ represent the same or different hydrogen atom, fluorine atom or chlorine atom, and at least one of ^{X 11} , X ²¹ , X ³¹ and X ^41. One represents a hydrogen atom and ^{at least one of X 11} , X ²¹ , X ³¹ and X ⁴¹ represents a fluorine atom)
Fluoroolefins represented by can be obtained.

In the hydrogen fluoride step, the method of the hydrogen fluoride reaction is not particularly limited, and for example, it can be carried out under the same conditions as the known defluorinated hydrogen reaction. For example, the hydrogen fluoride reaction can be carried out in the gas phase in the presence of a catalyst for hydrogen fluoride.

In the production method 2 of the present disclosure, the hydrogen fluoride reaction when 1,1,2-trifluoroethane (HFC-143) is used as the fluoroethane follows the following reaction formula.
CF ₂ HCPH ₂ → CHF = CHF + HF

The catalyst for hydrogen fluoride is not particularly limited, and known catalysts can be widely used, and examples thereof include chromium oxide, chromium fluoride oxide, aluminum oxide, and aluminum fluoride oxide.

The catalyst medium for hydrogen fluoride is preferably supported on a carrier. Examples of the carrier include carbon, alumina (Al ₂ O ₃ ), zirconia (ZrO ₂ ), silica (SiO ₂ ), titania (TIO ₂ ) and the like. As the carbon, activated carbon, amorphous carbon, graphite, diamond and the like can be used.

In the production method 2 of the present disclosure, the hydrogen fluoride reaction can also be carried out in the presence of an oxidizing agent. Examples of the oxidizing agent include oxygen, chlorine, bromine and iodine, and oxygen is particularly preferable. The concentration of the oxidizing agent is not particularly limited, and can be, for example, the same as that of a known defluorinated hydrogen reaction.

The reaction temperature of the hydrogen fluoride reaction is not particularly limited, and can be the same as that of a known hydrogen fluoride reaction, for example, 300 ° C. or higher, preferably 320 ° C. or higher, more preferably 340. The temperature can be set to ℃ or higher, particularly preferably 350 ℃ or higher. The reaction temperature of the hydrogen fluoride reaction can be 600 ° C. or lower, preferably 550 ° C. or lower, more preferably 500 ° C. or lower, and particularly preferably 450 ° C. or lower.

The reaction time of the defluorinated hydrogen reaction and the pressure at the time of the reaction are not particularly limited, and known conditions can be widely adopted. The defluorinated hydrogen reaction can be carried out in the presence of either an inert gas or air. As the defluorination hydrogen reaction, either a continuous method or a batch method may be adopted.

The production method 2 of the present disclosure may include, if necessary, other steps in addition to the hydrogen fluoride step. Also in the production method 2, the raw material can be separated from the crude product obtained in the production method 2 and recycled.

By the hydrogen fluoride step, the desired fluoroolefin, for example, the compound represented by the general formula (4) is obtained. The target fluoroolefin produced in the hydrogen fluoride step is one or more.

The resulting fluoroolefin can be determined by the fluoroethane used in the hydrogen fluoride step. Examples of fluoroolefins include 1,2-difluoroethylene (HFO-1132), 1,1-difluoroethylene (HFO-1132a) and trifluoroethylene (HFO-1123).

When HFC-143 is used as the fluoroethane in the production method 2 of the present disclosure, the obtained fluoroolefin is HFO-1132. When HFC-143a is used as the fluoroethane in the production method 2 of the present disclosure, the obtained fluoroolefin is HFO-1132a. When HFC-134 is used as the fluoroethane in the production method 2 of the present disclosure, the obtained fluoroolefin is HFO-1123. HFO-1132 may include trans-1,2-difluoroethylene [(E) -HFO-1132], cis-1,2-difluoroethylene [(Z) -HFO-1132].

When the fluoroolefin is obtained by the above-mentioned production method 2 of the present disclosure, the above-mentioned production method 1 of the present disclosure and the production method 2 of the present disclosure may be carried out continuously or independently. good.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the aspects of these Examples.

(Example 1)
One 50A reaction tube was prepared, and the reaction tube was filled with 670 g of catalyst. The catalyst was formed using activated carbon as a carrier and a noble metal as palladium. When the reaction tube is filled with the catalyst, the amount of palladium supported is 0.3% by mass with respect to the total mass of the catalyst, and the amount of palladium supported is 3% by mass with respect to the total mass of the catalyst. The catalyst was formed as a downstream part. Chlorotrifluoroethylene (hereinafter referred to as CTFE) is supplied at a flow rate of 500 Nml / min and hydrogen is supplied at a flow rate of 1800 Nml / min from the raw material supply port of the reaction tube filled with the catalyst in this order, in the order of the upstream portion and the downstream portion. The catalyst was passed. At this time, the temperature of the upstream portion was set to 320 ° C, and the temperature of the downstream portion was set to 230 ° C. In the above reaction, the charge amount of the catalyst in the reaction tube is W (g), the total flow rate of the fluoroethylene and hydrogen gas flowing into the reaction tube is Fo, and the contact time represented by W / Fo is 17 g · sec / cc. And said.

(Example 2)
One 50A reaction tube was prepared, and the reaction tube was filled with 670 g of catalyst. The catalyst was formed using activated carbon as a carrier and a noble metal as palladium. When the reaction tube is filled with the catalyst, the amount of palladium supported is 0.3% by mass with respect to the total mass of the catalyst, and the amount of palladium supported is 3% by mass with respect to the total mass of the catalyst. The catalyst was formed as a downstream part. Chlorotrifluoroethylene (hereinafter referred to as CTFE) is supplied at a flow rate of 500 Nml / min and hydrogen is supplied at a flow rate of 1800 Nml / min from the raw material supply port of the reaction tube filled with the catalyst in this order, in the order of the upstream portion and the downstream portion. The catalyst was passed. At this time, the temperature of the upstream portion was set to 250 ° C., and the temperature of the downstream portion was set to 160 ° C. In the above reaction, the charge amount of the catalyst in the reaction tube is W (g), the total flow rate of the fluoroethylene and hydrogen gas flowing into the reaction tube is Fo, and the contact time represented by W / Fo is 17 g · sec / cc. And said.

(Comparative Example 1)
One 25 L capacity reaction tube was prepared, and the reaction tube was filled with 810 g of catalyst. The catalyst was formed using activated carbon as a carrier and a noble metal as palladium, and the amount of palladium supported was 0.6% by mass with respect to the total mass of the catalyst. CTFE was supplied at a flow rate of 555 Nml / min and hydrogen was supplied at a flow rate of 1945 Nml / min from the raw material supply port of this reaction tube, and the catalyst was passed through. In the above reaction, the charge amount of the catalyst in the reaction tube is W (g), the total flow rate of the fluoroethylene and hydrogen gas flowing into the reaction tube is Fo, and the contact time represented by W / Fo is 19 g · sec / cc. And said.

Table 1 shows the results of gas chromatography in Examples and Comparative Examples.

From Table 1, in the hydrogenation reaction in which the upstream portion and the downstream portion were provided in the reaction tube as in Example 1, the selectivity of the target product, HFC-143, was high, and the intermediate product, fluoroethylene (fluoroethylene). It was found that the amount of HFO-1123) mixed in was small. Further, in Example 1, the mixing of other impurities was suppressed, and no corrosion of the reaction tube or clogging due to the polymer was observed even after 400 hours of operation. On the other hand, in Comparative Example 1, a polymer was formed, and the reaction tube was significantly clogged during the reaction. In Example 2, the reaction temperature was changed from that in Example 1, and it was also found that the HFC-143 and HFO-1123 contained in the product could be adjusted at an arbitrary ratio. In Example 2, no corrosion of the reaction tube or clogging due to the polymer was observed.

Claims (6)

The following general formula (1)
CX ¹ X ² FCX ³ X ⁴ X ⁵ (1)
(In formula (1), X ¹ , X ² , X ³ , X ⁴ and X ⁵ are the same or different and represent hydrogen, fluorine or chlorine atoms, X ¹ , X ² , X ³ , X ⁴ and at least one of X ⁵ represents a hydrogen atom)
It is a method for producing fluoroethane represented by
Depending on the reaction in the presence of a catalyst, the following general formula (3)
CX ⁹ F = CX ¹⁰ X ¹¹ (3)
(In formula (3), X ⁹ , X ¹⁰ and X ¹¹ represent the same or different hydrogen atom, fluorine atom or chlorine atom).
The step of obtaining the product containing the fluoroethane from the fluoroethylene represented by the above formula (3) is included, and the fluoroethylene represented by the above formula (3) contains chlorotrifluoroethylene.
The catalyst is formed by supporting a noble metal on a carrier.
The reactor in which the reaction is carried out is filled with a catalyst having a noble metal concentration of C1% by mass based on the entire catalyst and a catalyst having a noble metal concentration of C2% by mass based on the entire catalyst, respectively. A part is formed and C1 <C2.
A method for producing fluoroethane, wherein the reaction is carried out by bringing fluoroethylene and hydrogen gas represented by the formula (3) into contact with each other in the order of the upstream portion and the downstream portion. The method for producing fluoroethane according to claim 1, wherein the noble metal is palladium. The method for producing fluoroethane according to claim 1 or 2, wherein the fluoroethane comprises 1,1,2-trifluoroethane. The production method according to claim 3, wherein the product contains 60 mol% or more of 1,1,2-trifluoroethane based on the total amount of the product. The production method according to any one of claims 1 to 4, wherein the product contains 40 mol% or less of trifluoroethylene based on the total amount of the product. A method for producing a fluoroolefin, which comprises a step of obtaining a fluoroolefin by a defluorination hydrogen reaction of fluoroethane.
Depending on the reaction in the presence of a catalyst, the following general formula (3)
CX ⁹ F = CX ¹⁰ X ¹¹ (3)
(In formula (3), X ⁹ , X ¹⁰ and X ¹¹ represent the same or different hydrogen atom, fluorine atom or chlorine atom).
Including the step of obtaining the product containing the fluoroethane from the fluoroethylene represented by, the fluoroethane is the following general formula (1).
CX ¹ X ² FCX ³ X ⁴ X ⁵ (1)
(In formula (1), X ¹ , X ² , X ³ , X ⁴ and X ⁵ are the same or different and represent hydrogen, fluorine or chlorine atoms, X ¹ , X ² , X ³ , X ⁴ and at least one of X ⁵ represents a hydrogen atom)
Represented by
The fluoroethylene represented by the above formula (3) contains chlorotrifluoroethylene and contains chlorotrifluoroethylene.
The catalyst is formed by supporting a noble metal on a carrier.
The reactor in which the reaction is carried out in the presence of the catalyst is filled with a catalyst having a noble metal concentration of C1% by mass based on the entire catalyst and a catalyst having a noble metal concentration of C2% by mass based on the entire catalyst. Each forms an upstream part and a downstream part, and C1 <C2.
A method for producing a fluoroolefin , wherein the reaction in the presence of the catalyst is carried out by bringing fluoroethylene and hydrogen gas represented by the formula (3) into contact with each other in the order of the upstream portion and the downstream portion.